Bomb sight



y @Ross REFERENCE pri 5, 1938.- H- RAABER soma snm Filed Sept. 2e. 1934 Patented Apr. 5, 1938 vmuren STATES PATENT ori-lcs aussie anales BOMB SIGHT Hans Baaber, Purkersdorii, near Vienna, Austria,

assigner to Actiengeselischalt C. P.

Goerz Optische Anstalt Actiova Spolenost K. 'P. Goetz opticky ustav, Bratislava., Czechoslovakia, a company oi' Czechoslovakia Application September 28, 1934, Serial No. 746,021 Y. In Germany October 6, 1933 s claims. (C1. ca -46.5)

which if, as I prefer, the trail, i. e., the horizontal component of the movement oi the missile due to the resist-ance ci air is taken into account, is an proximateiy rectangular. One side of this` triangle is equal or proportional to said measured length while one oi the two other sides of said t triangle is inclined to the first named side of a 2 right angle and preferably at a right angle plus the range angle, its length being proportional to the measuring time taken at the scale o! adjust-v lng the upper sight mark in accordance with the falling time, that is to say, proportional to the time required for the apparent movement o! the target over the distance measured. The angle between the direction of the third side of the triangle, then resulting, then gives the range angle or the angle complementary thereto.

The accompanying drawing illustrates by way oi example two constructional forms or' the present apparatus. Fig. 1 illustrates the mechanical principle of the aiming device, Fig. 2 is a side elevation of the aiming device based on the principle illustrated in Fig. l, the adjusting screw spindle oi.' the releasing or dropping sight mark being vertical. Fig. 3 is a rear elevation of the device shown in Fig. 2. Fig. 4 illustrates the meo chanical principle oi the aiming device, the adjusting screw spindle of the releasing or dropping sight mark being horizontal. Fig. 5 is a side elevation of a smplied device with an invariable measuring distance.

45 In Fig. 1 the point O is an upper sighting mark.

the targetbeing at a distance H=OO3 below the aircraft-appears at Z1 in the rst preliminary sight. line and ends at the time t, when the target appears in the second sight line OA: in -I the point Zz. If in the horizontal line O-b a point B1 is so selected that OB1==A1A2=m and if the point B1 is moved vertically downwards f from the beginning of measuring witha constant speed -the trail being neglected-then this point will arrive at the end of the measuring time t at B: and B1B:=ct.

The angle OB2B1= is defined by the equation Now from the similar triangles OA1A2-OZ1Z2 it follows hzH=AlAzzZiZz==mznt and consequently is simply the tangent oi' the range angle so that the angle 0BaB1==Z30O3 is the range angle sought and OBnZa is the releasing or dropping sight line. For taking into account the trail angle p=OsOR the direction of movement ci' the point Bi would have to be at this angle to the vertical but turned backwards in order that the missile to be released may hit the point Zr which is in rear of the point Z3 that would be hit ln the absence of trail, being Z:Zr=O3R.

The apparatus illustrated in Figs. 2 and 3 and based on the above explained principle comprises a frame composed of two arms lvlh perpendicular to each other journalled in bracket 3 on the side wall of the aircraft by a hinge bolt 2 passing through the eyelets ia, is on said frame. A

vertical screw spindle l is rotatably mounted on i the vertical arm lv and a nut 5 locked against rotation is mounted on the screw spinale, is provided with a mark 5s serving for adjustment and vmoves along a scale on the arm Iv indicating falling time so that the nut 5 may be adjusted to any falling time.

Gn the 'horizontal arm are rotatably mounted two coaxial screw spindles El. 6iconnected by a clutch 6. On turning these screw spindles in the rst place the nut carrying the preliminary sight and locked against rotation on the right handed `screw spindle `il may be adjusted axially while at the same time th.: slide i movable along the horizontal arm In of the frame and connected with the nut 8. mounted on the left handed screwspindle 61 moves to the same extent but in the opposite direction The slide 8 carries a clockwork 9 rotating a shaft I8 with constant speed in the one or in the other direction according to whether the button 9v or 8: is pushed. On this shaft l0 is idly mounted a vertical arm H in which is journalled a screw spindle l2 serving as the adjusting spindle of the release or dropping sight mark. Moreover a bevel pinion I3 is fast on'the end of the shaft ID and engages into a bevel pinion I 4 fast on the screw spindle l2. On

the screw spindle l2 is mounted and locked against rotation a nut l5 -carrying the releasing sight Bz. In the lug son the slide 8 a clamping screw i6 is securedwhich engages into a slot Il. concentric to the shaft I0 so that by tightening the thumb nut the arm provided with the adjusting mark may be so clamped in position that the screw yspindle I2 may be inclined to the Avertical by, an angle equal to the trail angle.

The operation of the device 'is the following:

Prior to the beginning of measuring the sightf ing mark O carried by the nut 5 is adjustedin carried thereby being brought into the position Ai. It it is desiredto select at will the position ofthe sight mark the clutch E can be constructed so that the screw spindle 6r can be shifted without rotation and can be subsequently locked in position. Such constructions are conventional per se, as in drafting instruments. The aircraft then dies towards the target in an exactly hori- "zontal direction and the apparatus is so turned relatively to the wall of the aircraft that the target may come into the preliminary sight line,

'even in the cese of drift. At the moment it does so the button 9v is actuated, thereby starting shaft it of the clockwork to revolve in the forward direction. Thereby the nut i5 and the releesingsight mark B2 is moved downwards.

Ii because of clouds or for any other reason the target cannot be properly sighted at Z2, thenf after beginning ot the measurements the nut l is shifted to the left through any desired distance by turning' the 'knob 6. until the' target appears in the sighting line CA2. In this shifting movement the slide 8, together with the nut I5 and the mark Bz, is moved forward, so that by this operation the distance A1A: has been increased,v

although the point A1, which is no longer required has moved along with A2. 'At the moment when the target appears in the sighting line OA: the clockwork is stoppedby pressingthe button Sr. Thus the nut i5 and the dropping sight mark Bz are in such a position that the sight line DB2 makes with the vertical the range angle required for hitting the target. s

This aiming device becomes much simpler if a constant measuring distance is used. Then the two screw spindles Se and Bl may be dispensed with together with their actuating knob and' theirclutch S and the slide i?. Instead thereof "with the aid ofthe-adjusting .mark 5a.

two preliminaryisighting marks AiAalare providedon the horiaontal arm is of the frame in a properly selected distance from each other while the clockwork 9 is so arranged on this arm lh that the horizontal distance between the sight' marks O and B is equal to the distance between the sight-marks A1 and A1. The two sighting marks may then be arranged on a slide directly` moved by hand along the horizontal arm in in order to enable the first preliminary sighting direction to be selected at will, independent oi the falling time. that is to say, the vertical distance between the sighting mark O and the measuring line AlAa.

The operation of the simpliiied apparatus is simpler than that of the appara-tus hereinbei'ore described, vin so far that after starting the clockwork shaft at the moment of. the coincidence of the target with the first preliminary sighting line OA! no'further actuation is required except the throwing out of` operation of the clockwork shaft Iii at the moment oi.' coincidence of the second rotation and is guided on the vertical arm ivprovided with the scale for the falling time. On this scale the height oi. the sighting mark 0 above the measuring distanceI A1A: may be adjusted 'ine measuring distance A1A; is ,represented by the two preliminary sighting marks A1 and Asfast in a slide freely movable along the horizontal arm is and adapted to be locked in position. The bracket 5b on the nut 5 carries at B1 a-horizontal trunnion on 'which the clockwork casing 9 is journalled, OBl' being equal to AiAz.- Ilie reversible clockwork shaft i0' revolving at a constant speed may be thrown into and out of operation in the same manner as the shaft I8 in Figs.

. 2 and 3 and transmitsits revolution by the spur wheels I3', I4' to the horizontal'screw spindle I2' serving as the adjusting spindle oi the releasing sight mark. On this screw spindle is mounted a prismatic nut carrying a trunnion Bz' engaging into a slot of an arm I8.. of a rectangular toggle lever pivoted at O; `-'the other arm its of this lever carries the dropping mark 13a". The range angle o is in this case the angle Bi'OBz" complementary to the angle Bz'OBi' and is thus transmitted. This angle BzOBiis the opposite angle ofthe measuring' triangle of even name which isiormed when at the beginning of the measuring time, when Z1 is in the first preliminary sighting line DA1, the centre oi'. the pin Bz' wasv in CB1' so that after theespiretion of the measuring time t owing to the. rotation oi the clockwork shaft i0' having taken place during time has arrived in the position Bz shown, neglecting, however, trail. For taking into account the trail the clockwork .9' pivoied on B1' would 'have to be so turned by turning the screwl i9 in the arm le of the frame. until the adjust- 'ing spindle l2' makes the trail angle with the vstructional Iorm shown in 'Figs 2 and then the speed of the clockwork must be so contrclled that i B,B,=1.ct if c were equal to g1?! what I claim is: 1. An apparatus for determining the range angle for releasing missiles from aircrafts, comprising a frame, a iirst substantiallyV vertical screw spindle mounted on said frame, a first nut l threaded on said rst screw spindle and locked against rotation therewith, a sighting mark carried by said first nut and movable along said first screw spindle as said spindle is rotated, two preliminary sighting'marks on said frame, means for moving said preliminary sighting marks hori zontally along said frame a fixed distance from each other, a clockwork sldable on said frame, a second substantially vertical screw spindle on said clockwork, a second nut threaded on said second screw spindle and locked against rotation therewith, a release sighting mark connected with said second nut, and means including said clockwork for revolving said second screw spindle for a certain time as determined by said two pre-l liminary sighting marks at a constant angular speed, whereby after the expiration of said time said first-named sighting mark and said release sighting mark operate to indicate the angle sought.

2. .en apparatus for determining the range angie for releasing missiles from aircrafts, comprising a frame, a rst substantially vertical screw spindle mounted on said frame, a iirst nut threaded on said rst screw spindle and locked against rotation therewith, a sighting mark carried by said first nut and movable along said first screw spindle as said spindle is rotated, two preliminary sighting marks on said frame. a slide mounted on and movable along said frame, a clockwork mounted on said slide, a second mbstantially vertical screw spindle on said clockwork, means for holding said second screw spindie inclined to the vertical by the trail angle, a second nut threaded on said second screw spindle and locked against rotation therewith, a release sighting mark connected with said second nut, means including said clockwork for revolving said second screw spindle for a certain time as determined -by said two preliminary sighting marks at a constant angular speed, whereby after the expiration of said time said irst-named sighting mark and said release sighting mark cooperate to indicate the angle sought.

3. An apparatus for determining the range angle for releasing missiles from aircrafts, comprising a frame. a first lsuhstantially vertical screw spindle mounted on said frame, a rst nut threaded on said Iirst screw spindle and locked against rotation therewith, a sighting mark carried by said iirst nut and movable along said first screw spindle as said spindle is rotated, two preliminary sighting marks on said frame. a clockwork slidable on said frame, a second screw spindle on said'ciockwork, a second nut threaded on said second screw spindle and locked against rotation therewith, means operatively interconnecting said second nut and said release sighting mark .so that the latter is controlled by said second nut, and means including said clockwork for revolving said second screw spindle for a certain time as determined by said two preliminary sighting marks at a constant angular speed, whereby after the expiration of said time said iirst-named sighting mark and said release sighting mark cooperate to indicate the angle sought.

4. An apparatus for determining the range angle for releasing missiles from aircrafts, comprising a frame, a first substantially vertical screw spindle mounted on said frame, a rst nut threaded on said rst screw spindle and locked against rotation therewith, a rst sighting mark carried by said rst nut and movable along said first screw spindle as saidspindle is rotated, a slide, means for moving said slide horizontally along said frame, a preliminary sighting mark on said frame, a second sighting mark, Ameans for moving said second sighting mark horizontally along-saidframe ina direction opposite to the movement of said slide but to the same extent thereof, a clockwork on said slide, a second sub-l stantially vertical screw spindle on said slide, means whereby said clockwork rotates said second spindle, a. second nut threaded on said second screw spindle and locked against rotation therewith, a release sighting mark connected with said second nut, and means inrluding said clockwork for revolving said second screw spindle for a certain time as determined by said two preliminary sighting marks at a constant angular speed, whereby after the expiration of said time said rst-named sighting mark and said release sighting mark cooperate to indicate the anglev sought.

5. An apparatus for determining the range angle for releasing missiles from aircrafts, comprising a frame, a iirst substantially vertical screw spindle mounted on said frame, a rst nut threaded on said rst screw, two horizontal coaxial second and third screw spindles one of which is right-hand threaded and the other lefthand threaded, a second nut threaded on one of these coaxial screw spindles, and locked against rotation therewith, a slide secured cn said second nut, a third nut threaded on the other of said coaxial spindles and locked against rotation therewith, a second sighting mark on said third nut, a clockwork and a fourth substantially vertical screw spindle, both mounted on said frame, a fourth nut threaded on said fourth screw spindle and locked against rotation therewith, a release sighting mark connected with said fourth nut, and means including said clockwork for revolving said fourth screw spindle for a certain time as determined by said slide and said second sighting mark at a constant angular speed, whereby after the expiration of said time said first-named sighting mark and said release sighting mark cooperate to indicate the angle sought.

5. An apparatus for determining the range angle for releasing missiles from aircrafts, comprising a frame, a first substantially vertical screw spindle mounted on said frame, a rst nut threaded on'said first screw, two horizontal coaxial second and third screw spindles on said frame. one of which is right-hand threaded and the other left-hand threaded, a nut threaded on theorie of these coaxial screw spindles, and locked against rotation therewith, a slide secured on saidsecond nut, a third nut threaded on the other of these coaxial screw spindles and locked against rotation therewith, a sighting mark on said third nut, a clockwork on said slide, a fourth screw spindle pivotally aiiixed to said slide to swing-in the vertical plane screw spindie andk locked against rotation therewith, a. release sighting mark connected with said fourth nut, and means including said clockwork rior revolving said fourth screw spindle for a. certain time as determined by said slide and said second sighting mark at a constant angular speed,

ywhereby after the expiration of said time said `irst-:naxmed sighting mark and said release sghting mark cooperate to indicate the angle sought. 5

HANS RAABER. 

